Recently, I had the opportunity to
work with MySQL and successfully implement it in a project. As part of sharing
my experience, I decided to write a blog series on MySQL. In this article, I
will explain how to install and configure MySQL on an Oracle Linux server in a
simple and easy-to-follow manner.
MySQL is one of the most widely used
open-source relational database management systems (RDBMS). It is commonly used
for websites, business applications, and other data-driven solutions because it
is reliable, scalable, and easy to manage.
Oracle Linux is a secure and stable
operating system that provides an excellent platform for running MySQL
databases. Due to its performance and enterprise-level features, many
organizations choose Oracle Linux for their database environments.
In this blog, we will go through the
step-by-step process of installing and configuring MySQL Server on an Oracle
Linux server, helping you get your database environment up and running quickly.
 |
| MySQL Client-Server Architecture |
MySQL
uses a client-server architecture. The MySQL Client connects to the MySQL Server using
the default port 3306. The server receives and processes SQL
queries, then sends the results back to the client. All databases, tables, and
log files are stored in the /var/lib/mysql data directory.
Prerequisites
Before you begin, ensure you have:
- An Oracle Linux 8 or Oracle Linux 9
server
- Root or sudo privileges
- Internet connectivity to download
packages
- At least 8 GB RAM (recommended)
- Open port 3306 (if remote access is needed)
Step 1: Update the System
It is
always a good practice to update the system packages before installing any new
software. For this use below command,
sudo dnf update -y
Verify the
Oracle Linux version:
cat /etc/os-release
Sample output:
NAME="Oracle Linux Server"
VERSION="9.3"
Step 2: Check Existing MySQL Packages
Verify whether MySQL is already
installed.
rpm -qa | grep mysql
If old MySQL packages exist, remove them
if necessary.
sudo dnf remove mysql*
Step 3: Install MySQL Repository
Download
and install the MySQL Community Repository package.
For Oracle Linux 8/9:
sudo dnf install https://dev.mysql.com/get/mysql84-community-release-el9-1.noarch.rpm
-y
For Oracle Linux 8, use the appropriate
EL8 repository package.
Verify enabled repositories:
sudo dnf repolist enabled | grep mysql
Step 4: Install MySQL Server
Install MySQL Server using DNF.
sudo dnf install mysql-community-server
-y
This command installs the MySQL Server package and its required dependencies.
Verify installation with below commands:
systemctl status mysqld
mysql --version
Example output:
mysql Ver 8.4.0 for Linux on x86_64
Step 5: Start and Enable MySQL Service
Start the MySQL service:
sudo systemctl start mysqld
Enable MySQL to start automatically after
reboot:
sudo systemctl enable mysqld
Check service status:
sudo systemctl status mysqld
Expected output:
Active: active (running)
Step 6: Retrieve the Temporary Root Password
During
installation, MySQL generates a temporary root password.
Retrieve
it from the log file:
sudo grep 'temporary password'
/var/log/mysqld.log
Example:
A temporary password is generated for
root@localhost: Xyz#123Abc
Make a note of this password.
Step 7: Secure the MySQL Installation
Run the below
MySQL security script.
sudo mysql_secure_installation
The script
will prompt you to:
Enter
temporary root password
Set a new
root password
Remove
anonymous users
Disable
remote root login
Remove
test database
Reload privilege tables
Example interaction:
Securing the MySQL server deployment.
Enter password for user root:
New password:
Re-enter new password:
Remove anonymous users? (Y/N): Y
Disallow root login remotely? (Y/N): Y
Remove test database and access to it?
(Y/N): Y
Reload privilege tables now? (Y/N): Y
Step 8: Login to MySQL
Connect to MySQL as root.
mysql -u root -p
Enter the password configured in the
previous step.
Verify:
SELECT VERSION();
Show more lines
Example output:
+-----------+
| VERSION() |
+-----------+
| 8.4.0 |
+-----------+
Exit MySQL:
EXIT;
Now What's Next?
Step 9: Create a Database and User
Create a database:
CREATE DATABASE companydb;
Create a dedicated user:
CREATE USER 'dbadmin'@'localhost'
IDENTIFIED BY 'StrongPassword@123';
Grant privileges:
GRANT ALL PRIVILEGES ON companydb.* TO
'dbadmin'@'localhost';
FLUSH PRIVILEGES;
Verify user creation:
SELECT user, host FROM mysql.user;
Step 10: Configure Remote Access (Optional)
If
applications need to connect remotely to MySQL, perform the following
configuration.
Modify
MySQL Configuration
Edit the MySQL configuration file:
sudo vi /etc/my.cnf
Locate:
bind-address=127.0.0.1
Replace with:
bind-address=0.0.0.0
Save and restart MySQL:
sudo systemctl restart mysqld
Now Create
Remote User
CREATE USER 'remoteuser'@'%'
IDENTIFIED BY 'StrongPassword@123';
GRANT ALL PRIVILEGES ON companydb.* TO
'remoteuser'@'%';
FLUSH PRIVILEGES;
Make sure
to open Firewall Port, allow MySQL traffic through firewall.
sudo firewall-cmd --permanent
--add-service=mysql
sudo firewall-cmd --permanent --add-port=3306/tcp
sudo firewall-cmd --reload
Verify:
sudo firewall-cmd --list-services
sudo firewall-cmd --list-ports
Step 11: Verify Connectivity
From any another system having mysql
client:
mysql -h <server-ip> -u remoteuser
-p
Example:
mysql -h 192.168.1.100 -u remoteuser -p
If successful, you should receive the
MySQL prompt:
mysql>
Step 12: Configure Automatic Backups
Create a backup directory:
mkdir -p /backup/mysql
Take a manual backup:
mysqldump -u root -p companydb >
/backup/mysql/companydb.sql
Create a cron job:
crontab -e
Add:
0 1 * * * mysqldump -u root
-p <YourPassword companydb > /backup/mysql/companydb_$(date +\%F).sql
This backup runs daily at 1:00 AM.
Here, we installed MySQL on Oracle Linux, started the service, secured the root account, and verified the installation.
Best Practices
Use strong
passwords for all database accounts.
Avoid
using the root account for applications.
Enable
regular database backups.
Keep
Oracle Linux and MySQL updated with security patches.
Restrict
remote access to trusted IP addresses only.
Monitor
database logs regularly.
Use
SSL/TLS encryption for database connections.
Common Errors:
Service won't start
If the MySQL service fails to start after installation, first check its current status.
sudo systemctl status mysqld
If the service is not running,
review the detailed error messages in the MySQL error log.
sudo cat /var/log/mysqld.log
Common causes and solutions
1] Data directory is not initialized
Error: mysqld: Data Dictionary initialization failed
Solution:
sudo mysqld –initialize
or (for insecure initialization)
sudo mysqld --initialize-insecure
Then start the service again.
sudo systemctl start mysqld
2]. Port 3306 is already in use
Check whether another application is using port 3306.
sudo ss -tulnp | grep 3306
If another MySQL instance is
running, stop it or change the MySQL port in the configuration file.
3]. Incorrect permissions on the data directory
ls -ld /var/lib/mysql
If required, correct the ownership.
sudo chown -R mysql:mysql /var/lib/mysql
4]. SELinux restrictions (Oracle
Linux)
If SELinux
is enabled, it may prevent MySQL from accessing required files or directories.
Check the SELinux status.
getenforce
If necessary, review the audit logs or temporarily set SELinux to permissive mode for testing.
sudo setenforce 0
Note: This is intended only for troubleshooting. After identifying the issue, configure the appropriate SELinux policies instead of leaving SELinux in permissive mode.
After resolving the issue, reload the service configuration and start MySQL.
sudo systemctl daemon-reload
sudo systemctl restart mysqld
Verify that the service is running.
sudo systemctl status mysqld
A successful start should show:
Active: active (running)
Temporary root password not found
After
installing MySQL, the initial root password is usually generated automatically
and stored in the MySQL error log.
sudo grep 'temporary
password' /var/log/mysqld.log
Expected
output something like:
A
temporary password is generated for root@localhost: Abc#1234xyz
If no
password is found,
Verify
that the MySQL service started successfully
The
temporary password is generated only during the initial startup.
If the
temporary password cannot be recovered, you can reset the MySQL root password
by starting MySQL in safe mode (or with --skip-grant-tables), changing
the password, and then restarting the service normally.
Note : Resetting
the root password should be used only when the original temporary password is
unavailable or has been lost.
For a new
installation, the quickest way to retrieve the temporary password is :
sudo grep 'temporary
password' /var/log/mysqld.log
If no
output is returned, first confirm that MySQL started successfully and that this
is truly a fresh installation. In many cases, the absence of a temporary
password indicates that the data directory was already initialized or that
MySQL was installed using the --initialize-insecure option.
Conclusion
Installing MySQL Server on Oracle Linux is a straightforward process when following the correct steps. By updating the system, installing MySQL packages, securing the installation, configuring users, and enabling backups, you can create a reliable and secure database environment. Proper configuration and regular maintenance will ensure optimal performance and data protection for your applications.
Thanks for reading!
Stay tuned
with itsdbaworld for upcoming blogs,
- How we
can take backups of MySQL Database “
- Restore
and Configure MySQL Database from backup
- Clone
and Configure MySQL Database from backup on an different Oracle Linux server
- Install and Configure MySQL on an Oracle Linux Server Introduction
